An Automated Analyzer for Financial Security of Ethereum Smart Contracts

At present, millions of Ethereum smart contracts are created per year and attract financially motivated attackers. However, existing analyzers do not meet the need to precisely analyze the financial security of large numbers of contracts. In this paper, we propose and implement FASVERIF, an automated analyzer for fine-grained analysis of smart contracts' financial security. On the one hand, FASVERIF automatically generates models to be verified against security properties of smart contracts. On the other hand, our analyzer automatically generates the security properties, which is different from existing formal verifiers for smart contracts. As a result, FASVERIF can automatically process source code of smart contracts, and uses formal methods whenever possible to simultaneously maximize its accuracy. We evaluate FASVERIF on a vulnerabilities dataset by comparing it with other automatic tools. Our evaluation shows that FASVERIF greatly outperforms the representative tools using different technologies, with respect to accuracy and coverage of types of vulnerabilities

Hybrid Metaheuristics and their Implementations

This paper studies with the design of hybrid metaheuristics and their implementations. Hybrid metaheuristics involve some major issues that could be classified as design and implementation. Combining different kinds of methods is a ordinary strategy to solve optimization problems. As we have developed a unified view of metaheuristics, that is based on their key search components, one can say that designing a multi-objective metaheuristic can be reduced to select the most suited search components and combining them. Each of these metaheuristics has been proven successful on a variety of applications. Although there have been attempts to compare their performance, the results are contradicting and inconclusive. A difference is made between the design issues used to introduce hybridization and implementation issues that depend on the execution model of the algorithms

Modeling and Development of Medical Information System Based on Support Vector Machine in Web Network

This paper aims at improving and utilizing the ontology information in ontology design of FOAF and vCard in real time, and the application of open relational data technology, SPARQL query information results and sending RDF/JSON data format. In addition, improve the effectiveness and efficiency of patient information extraction from the medical information website. This article includes two web search engines that are used to inform patients about medical care information. The experiment uses Drupal as the main software tool, and the Drupal RDF extension module provides some meaningful mapping. In the evaluation part, the structure of the experimental test platform is established and the system function test is carried out. The evaluation results include consumers or patients retrieving the latest doctor information and comparing search capabilities and techniques, between our system and existing systems

Observations on the Hybrid F of Trachypthecus leucocephalus and T. francioisi and Its Offspring

The characteristics and behaviours of F1f (the female hybrid of Trachypithecus leucocephalus and T. francoisi) and its backcross offspring (Be1， Be2， Be3 and Be4) were extensively observed. The results showed that the hybrid F1f and its offspring had similar characteristics with T. francoisi. Besides the black hair was an overwhelmingly dominant character, the changing of their hair colour, the breeding behaviour of hybridized F1，and the growing process and behaviours of the hybrid F1f offspring resembled T. francoisi. However the feature of T. leucocephalus was nearly not present in the hybrid F1 and its offspring, excepting that in the development process the time for their hair colour change was longer and during their growth there existed imprinting phenomenon of T. leucocephalus. Therefore it can be inferred that the gene control of T. leucocephalus only played a supporting role and T. francoisi's gene dominated in the hybrid F1f and their offspring. The percent of weak infants for backcross langurs reaching 50%, which was higher than that of the general 10%-20% of T. francoisi, suggested a sign of outbreeding depression. Based on our observation that the hybrid F1f was able to reproduce its offspring successfully we can make a conclusion that T. leucocephalus should be considered as a subspecies of T. francoisi instead of an independent species

A Quantitative Method for the Composition of 7B05 Cast-Rolled Aluminum Alloys Based on Micro-Beam X-ray Fluorescence Spectroscopy and Its Application in Element Segregation of Recrystallization

Microscopic content segregation is among the important reasons for the anisotropy of mechanical properties in the cast-rolled sheets of the 7B05 aluminum alloy. It is of great significance to study the uniformity of aluminum alloys in terms of the microscopic composition and structure. In this study, a precise method for composition quantification based on micro-beam X-ray fluorescence spectroscopy is established by parameter optimization and a calibration coefficient. Furthermore, this method was applied for exploring and quantifying the relationship between recrystallization and deformation microstructures. The results show that the comprehensive measurement effects of all elements are the best when the X-ray tube voltage is 50 kV, the current is 150 μA, and the single-pixel scanning time is 100 ms. After verification, the sum of differences between the measured values and the standard values for all elements using the calibration coefficient is only 0.107%, which confirms the accuracy of the optimized quantitative method. Three types of segregation indexes in national standards were used to capture small differences, and finally ensure that the segregation degrees of elements are Ti > Fe > Cr > Cu > Mn > Zr > Zn > Al. The quantitative segregation results obtained by the spatial-mapping method show that the difference in the content of Al and Zn is approximately 0.2% between the recrystallization region and the deformation region, the difference in the content of Fe and Ti is 0.018% and 0.013%, the difference in the content of Cr, Cu and Zr is approximately 0.01%, and the difference in the content of Mn is not obvious, only 0.004%

Correlation among Composition, Microstructure and Hardness of 7xxx Aluminum Alloy Using Original Statistical Spatial-Mapping Method

The quantitative study of the relationship between material composition, microstructure and properties is of great importance for the improvement in material properties. In this study, the continuous data of elemental composition, recrystallization, hardness and undissolved phase distribution of the same sample in the range of 60 to 150 square millimeters were obtained by high-throughput testing instrument. The distribution characteristics and rules of a single data set were analyzed. In addition, each data set was divided into micro-areas according to the corresponding relationship of location, and the mapping between multi-source heterogeneous micro-area data sets was established to analyze and quantify the correlation between material composition, structure and hardness. The conclusions are as follows: (1) the average size of the insoluble phase in the middle of the two materials is larger than that of the surface, but due to the existence of central segregation, the average area of the T4 insoluble phase showed an abnormal decrease; (2) there was positive micro-segregation of Al, Cr, Ti, and Zr elements, and negative micro-segregation of Zn, Cu, and Fe elements in the recrystallized grains of the T5 middle segregation zone; (3) the growth process of the insoluble phase was synchronous with the recrystallization proportion and the size of the recrystallized grains; (4) the composition segregation and recrystallized coarse grains were the main reasons for the formation of low hardness zone in T4 and T5 materials, respectively